Fuel-burning heater for air and/or water



June 12, 1951 DAV|D50N 2,556,170

FUEL BURNING HEATER FOR AIR AND/OR WATER INVENTOR. LOLS @au 5m June 12, 1951 L. DAvlDsoN FUEL BURNING HEATER RoR AIR AND/0R WATER 3 Sheeis-Sheet 2 Filed Feb. 26, 1946 NVENTOR. lous csaz-z June 12, 1951 L, DAVIDSON 2,556,170

FUEL BURNING HEATR FOR 4AIR AND/0R WATER Filed Feb. 26, 1946 3 Sheets-She'et 5 1N VEN TOR. Loli/5' .Dawg/ogen Patented June v12, `T951 UNITED ASTATES PATENT OFFICE FUEL-BURNING HEATER FOR AIR AND/ R WATER The present invention relates 4to heaters, and it relates more particularly `to space-heaters adapted to supply heated air and/or water.

The object of the present invention is to `provide a new and improved construction for heaters. Another object of the present invention is to provide a new ,heater construction which is adapted more effectively to utilize the heat-ofcombustion of the fuel. Still another object of the present invention is to provide a heater adapted .for furnishing lhot air and/or water, wherein the combustion gases are led along a generally downward reverse-flow tortuous path So as to Agive more effective heat-transfer. A further object of the present invention is to provide a heater wherein combustion gases are led through a reverse-flow conduit constructed and arranged to permit heat to be transferred from the combustion gases to the uid being heated along both the inner and outer sides of the conduit. A still further object of the `present invention is to provide a relatively `simple and inexpensive, and yet eilicient, construction for spaceheaters or the like.

Other objects and advantages of the present invention are apparent in the following detailed description, appended claims, and accompanying drawings.

For the purpose of illustrating the invention, there are shown in the accompanying drawings forms thereof which are at present preferred, although it is to be understood that the various instrumentalities of which the invention consists can be variously arranged and organized and that the invention is not limited to the precise arrangements and organizations of `the instrumentalities as herein shown and described.

Referring to the accompanying drawings, in which like reference characters indicate like parts throughout:

Figure 1 represents a perspective view of one embodiment of the present invention, parts being broken away better to reveal the construction thereof.

Figure 2 represents a perspective view, gen-` erally similar to that of Figure l, but showing another embodiment of the present invention.

Figure 3 represents a horizontal cross-sectional view, generally along the line 3--3 `of Figure 2.

Figure 4 represents a perspective view of still another embodiment of the present invention, parts being broken away better to reveal the construction thereof.

Figure 5 represents a horizontal cross-'sec- `tional view generally on line 5-5 of Figure 4.

.In one embodiment of the present invention shownin Figure -1, I may provide a combination hot-airand hot-water heater which includes an `outer Ijacket or housing lill of sheet-metal or any other suitable material.

The jacket I0 may include a hot-air heating compartment II which may be lined with any suitable heat-resistant insulating material I2, and a cold-air inlet compartment I3, compartyments `II and I3 `being separated by a vertical Vwall rI 4.

A casingforming an enclosed combustion com partment I5 is disposed within the air-heating `compartment I I, `a lining I6 of `fire-brick being provided within `the lowermost portion of the combustion Vchamber I5.

A generally cylindrical upright hot-Water tank Il `is disposed, :for the most part, within the casing I5 and extends upward therebeyond, and through the upper part of the air-heating compartment LI I, the upper end of the tank 1I'I` extending above the top of the housing I0 and being provided with a hot-water outlet line I8. The bottom wall of the hot-water tank Il :is disposed isomewhat above the bottom of the combustion compartment I5 (the bottom of the tank I1 being generally level with the top of the lirebrick lining I6).

An oil-burner is disposed outside and in iront of the housing In with its barrel or nozzle 2|] extending through the housing and into the combustion compartment I5. Thus, the combustion gases 2I from `the barrel 20 are first directed, in large part, underneath the `'bottom of the hotwater tank JII and then are deflected `back by the lining I6 to rise upward within said combustion compartment I5.

The innermost end of the combustion compartment I5 is formed as a generally-rounded shell-.or sleeve 22 surrounding the hot-water tank I1.

The shell 22, which, with the `outer wall of the tank I'I, provides a generally enclosed hollow heat-exchange shell structure, has a vertical bafe 23 which is disposed generally at the median plane of the shell and which divides the shell into left and right halves which are provided with left and right inlet 'openings 214 and 25, respectively, disposed generally adjacent the top of the `combustion compartment l5. The combustion gases moving upward within the compartment I5 enter the left and right inlet openings 2l and "25 and move generally hori-4 zontal within the circular passageways 26 and- 2l e,556,17o f 3 dened by the top and sides of the shell 22 and by left and right curved horizontal battles 21a and 23, respectively.

The combustion gases move along the passageways 23 and 21 until they strike the left and right sides, respectively, of the uppermost end of the vertical baffle 23, the combustion gases moving generally clockwise within the left passageway 25 for somewhat more than 90 degrecs of arc, and moving counter-clock-wise through the right passageway 21 for a similar distance.

The left and right horizontal battles-21a and 28 extend from the inlet openings 24 and 25, respectively, to points somewhatI short of vertical baffle 23 so that the combustion gases striking the upper end of the vertical baffle are deected downward thereby to lower left and right horizontal passageways 29 and 3l) formed by the sides of the shell 22, the top horizontal bales 21a and 28 and by left and right horizontal baffles 3l and 32 which extend from the vertical baiiie '23 to pointsrsomewhat short of left and right clean-out doors 33 and 34 which are provided in front faces of the shell 22 and which extend downward from the left and right inlet openings 24 and 25 thereof.

Thecombustion gases thus deflected by the .vertical baffle 23 move counter-clockwise within the left passageway 29 until they strike the clean-out door 33 and are again deected downward thereby through the opening which results 'from the fact that the horizontal baffle 3l terminates short of the door 33.

Similarly, the combustion gases deiiected downward by the vertical baille 23 pass clockwise through the passageway 33 until they strike the clean-out door 34 and are deected downward thereby through the opening provided by the fact that the horizontal baille 32 terminates short of the clean-out door 34.

The vertical baie 23 terminates at the horizontal bales 3l and 32. Y

Thus, the gases deected downward by the clean-out doors 33 and 34 move along a lowertinuous contact with the hot-water tank I1, it

is obvious that passage of combustion gases through said shell 22 heats the water 31 in said tank.

Cold air is sucked into the compartment I3 nthrough an uppermost inlet opening 38 therein by a blower 33 disposed within said compartment I 5, the cold air being forced by said blower through a duct 43 into the air-heating compartment II.

The air passes through the compartment II in Vthe direction indicated by the arrows 4I and emerges, heated, through an uppermost outlet opening 42 formed in said compartment II.

During such passage the air is heated by the curved outer wall of the shell 22 and is also heated by the generally plane vertical side walls 43 of the combustion compartment I5 as well l as by the front wall 44 of said compartment I5 (which is spaced somewhat apart from the front 4 wall of the housing I0) and also by the top horizontal wall 45 of said compartment I5 (which is spaced somewhat below the top of housing IIJ).

The front wall 46 of the housing Ii) is provided with a door 41 which communicates with the combustion compartment I5 and which permits said combustion compartment to be cleaned out and which also gives access to the clean-out doors 33 and 34.

While vthe openings 38 and 42 are shown, in Figure 1, as communicating directly with the room in which the heater is installed, it is obvious that suitable conduits could be connected to the openings 3S and 42 to conduct the hot air to various rooms in a building or the like and to return the air from said rooms to the heater for re-circulation.

A Vwater-inlet pipe 48 extends through the housing I@ into the compartment I I and through the lowermost portion of the shell 22 to communicate with the bottom of the hot-water tank I1. To the water-inlet pipe 43 can be connected a valved return pipe 49 as well as a valved freshwater pipe 58.

The novel construction described above gives efficient heating of both air and water since a large area of heat-transfer surface is provided lfor both the water and air and since the re- -vice versa, depending Vupon whether the water 31 or the air 4I is warmer) While, for purposes of illustration, I have shown the unit as provided with an oil burner, it is apparent that other heating means could be employed (such as coal, gas or the like) without departing from the spirit of the present invention.

It is also apparent rthat the novel heater of the present construction can be provided with any suitable thermostatic controls to regulate lthe oil-burner and the temperature of the hot air and water.

I may also provide suitable insulating material, such as asbestos, magnesia, etc. upon the upper side of the bottom wall of the shel1k22 as well as upon the inner Sides of the clean-out plates 33 and 34 to lprevent excessive heattransfer from the flames in the combustion chamber tothe inside of the shell 22.

It is obvious, of course, that the tank I1, in-

stead of being circular in cross section may be made oval or any other suitable shape without departing from the spirit of the present invention.

AnotherV embodiment of the present invention y is shown in Figures 2 and 3. This embodiment generally resembles that of Figure l as described hereinabove, except that, in place of the hotwater tank I1, a generally cylindrical center hotair compartment 5I is provided. The hot-air compartment 5i is enclosed, for the most part, by the shell 22, as in the embodiment of Figure l, and extends to the top of the combustion com-- partment I5 where it communicates with the main air-heating compartment I I.

'In the embodiment of Figures V2 and 3 a gen-- erally horizontal air-conduit 52 passes through the lower portion of the shell 22 and connects the center compartment 5I with the main air-heating compartment I I so that air forced in through the duct 4i) by the blower 39 passes into the center compartment 5I as well as into the main airheating compartment I I.

In the embodiment of Figures 2 and 3 the housing or jacket Illa, is provided with a hot-air outlet opening 42a, disposed generally above the top of the center compartment 5I, in addition to the outlet openingillZ which is positioned genu erally similarly to that of Figure l.

Figure 3 shows the path of the combustion gases through the shell 22, this path being generally the same as in the embodiment of Figure l, as described hereinabove.

Still another embodiment of the present invention is shown in Figures 4 and 5.

This embodiment is designed to provide hot water exclusively and includes a housing or jacket 53 which forms a main water-heating compartment and is adapted to be filled with water and, therefore, is of heavier construction than the housing Ill of the embodiment of Figure 1.

Within the housing 53 are provided a combustion compartment I5 and a central hot-water tank Il! which are generally identical with the corresponding parts shown in Figure l, except that the combustion compartment I5 is also of heavy construction to withstand the pressure of the water in the housing 53.

Water is introduced into the housing 53 through inlet line 54 (which may be connected to a return line from the heating system and/or toa fresh-water inlet). Another inlet line 55 passes through the housing 53 and the shell 22 and connects with the central hot-water tank Il near the bottom thereof. Instead of the separate inlet line 55 .it is possible simply to provide a conduit (similar to the conduit 52 shown in Figure 2) which passes through the shell 22 and connects the center tank I I to the main hotwater compartment.

However, where the water heated in the outer compartment and in the `center tank I1 are adapted for diierent uses (as for example where the hot water from the outer compartment is intended for circulation through a hot-water radiator heating system; and where the water from the center tank I'i is led to hot-water faucets or the like) it is desirable that separate inlet lines 'et and 55 be provided, inasmuch as the inlet line 5d may provide simply for recirculation (and with occasional addition of fresh water to make up for leakage) while the inlet line 55 may provide for continuous introduction of fresh water to the tank E'I as the hot water drawn from said tank il is used-up.

rIhe tank Il' may be provided with a hot-water outlet line I8 (which may be similar to the outlet line It of Figure l but which may be somewhat larger in diameter to give greater flow-capacity). The top of the housing 53 may also be provided with an outlet line 56 through which the heated water from the main water compartment is led to a rem-cte space-heating system or the like.

In the embodiment of Figures 4 and 5, the inlet compartment I3 and the blower 39 are, of course, eliminated since no air is heated. In-

stead, the flue-pipe 36 passes through the back wall ofthe housing 53, a suitable duid-tight gasket 5'! being provided therefor.

While, in the embodiments of Figures 1 and 4, the central hot-water tank I'I is shown `as extending to the top of the combustion chamber or compartment I5, it is obvious that said tank could be made to terminate at the top of said chamber or compartment I5 (in which case the outlet line I 8 would `extend through the outer housing).

Vertical battle 23 divides the shell 22 into left and right halfsections, in each of which the combustion gases are led along a generally downward reverse-flow path through the verticallyseparated `connected horizontal passageways formed by the horizontal baflies 21, 28, 3| and 32.

As stated hereinabove, this downward reverse-V ilow movement of the combustion gases, which is counter-current to the generally upward movement of the heat-transfer fluids within the outer heating compartment and the inner tank I'I (or the compartment I5) provides more efrective heating of the air and/or water.

The present invention may be embodied in other speciiic forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiments be considered in all respects as illustrative and not restrictive, reference being had to the appended claims rather than to the foregoing description to indicate the scope of the invention.

Having thus described my invention, I claim as new and desire to protect by Letters Patent:

l. A heater comprising a jacket forming a hotheating compartment, a casing disposed in spaced relationship within said jacket and forming enclosed combustion compartment, a burner operatively connected to said combustion compartment and constructed and arranged to produce combustion gases therewithin, an upright generally cylindrical hot-water tank disposed, in most part, within said casing but extending upward therebeyond and through the upward portion of said hot-air heating compartment, a generally enclosed hollow heat-exchange shell structure being formed by said hot-water tank and the adjoining portion of said casing, a vertical baille disposed generally at the median piane of the shell structure and dividing it into left and right half-sections provided with separate uppermost inlet openings, said shell structure being provided with a lowermost outlet opening disposed below the lower end of the vertical bailie and communicating with both or" the halfsections, and at least one curved generally horizontal baille disposed within each of said halfsections and forming a plurality of vertically spaced communicating horizontal passageways therewithin, each of said half-sections being constructed and arranged to receive combustion gases through its uppermost opening and to conduct said gases along a generally downward tortuous path to said outlet opening so as to heat both the hot-air heating compartment and the hot-water tank.

2. A heater comprising a jacket forming a hotair heating compartment, a casing disposed in spaced relationship within said jacket and forming an enclosed combustion compartment, a burner operatively connected to said combustion compartment and constructed and arranged to produce combustion gases therewithin, an upright generally cylindrical hot-water tank disposed, in most part, within said casing but extending upward therebeyond and through the upper portionrof'said hot-air heating compartment, the bottom of said hot-water tank being disposed somewhat above the bottom of the combustion compartment whereby combustion gases are rst directed, in large part, underneath the bottom of the hot-water tank and are then deilecte'd back to rise upward within the combustion compartment, a generally enclosed hollow heatexchange shell structure being formed by said hot-water tank and the adjoining portion of said casing, a vertical baille disposed generally at the median plane of the shell structure and dividing it into left and right half-sections provided with separate uppermost inlet openings, said shell structure being provided with a lowermost outlet opening disposed below the lower end of the vertical baffle and communicating with both of the half-sections, and at least one curved generally horizontal baiile disposed-within each of said half-sections and forming a plurality of vertically spaced communicating horizontal passageways therewithin, each of said half-sections being constructed and arranged to receive combustion gases through its uppermost opening and to conduct said gases along a generally downward tortuous path to said outlet opening so as to heat both the hot-air heating compartment and the hot-water tank.

3. A heater comprising a jacket forming a hotair heating compartment, a casing disposed in spaced relationship within said jacket and forming an enclosed combustion compartment, a burner operatively connected to said combustion compartment and constructed and arranged to produce combustion gases therewithin, an upright generally cylindrical hot-water tank disposed, in most part, within said casing but extending upward therebeyond and through the upper portion of said hot-air heating compartment, a generally enclosed hollow heat-exchange shell structure being formed by said hot-water tank and the adjoining portion of said casing, a vertical baffle disposed generally at the median plane of the shell structure and dividing it into left and right half-sections provided with separate uppermost inlet openings, said shell structure being provided with a lowermost outlet opening disposed below the lower end of the vertical baille and communicating with both of the halfsections, each of said half-sections being provided with a plurality of generally horizontal curved baflles forming a plurality of generally horizontal Vvertically-spaced passageways within each of said half-sections, successively downward passageways communicating with each other at alternate ends, each of said half-sections being constructed and arranged to receive combustion gases through their uppermost openings and to conduct said gases along a generally downward tortuous path to said outlet opening thereby to heat boththe hot-air heating compartment and the hot-water tank.

4. A heater comprising a jacket forming a hotair heating compartment, a casing disposed in spaced relationship within said jacket and forming an enclosed combustion compartment, a burner operatively connected to said combustion compartment and constructed and arranged to produce combustion gases therewithin, an upright generally cylindrical hot-water tank disposed, in most part, within said casing but eX- tending upward therebeyond and through the upper portion of said hot-air heating compartment, the bottom of said hot-water tank being disposed somewhat above the bottom of the combustion compartment whereby combustion gases are first directed, in large part, underneath the bottom of the hot-water tank and are then deflected back to rise upward within the combustion compartment, a generally enclosed hollow heat-exchange shell structure being formed by said hot-water tank and the adjoining portion of said casing, a vertical baie disposed generally at the median plane of the shell structure and dividing it into left and right half -sections provided with separate uppermost inlet openings, said shell structure being provided with a lowermost outlet opening disposed below the lower end of the verf tical baffle and communicating with both of the half-sections, each or said half-sections being provided with a plurality of generallyrhorizontal curved bales forming a plurality of generally horizontal vertically-spaced passageways within each of said half-sections, successively downward passageways communicating with each other at alternate ends, each of said half-sections being constructed and arranged to receive combustion gases through their uppermost openings and to conduct said gases along a generally downward tortuous path to said outlet opening thereby to -heat both the hot-air heating compartment and the hot-water tank. Y

5. A heater comprising a jacket forming an outer heating compartment, a casing disposed in spaced relationship within said jacket and forming an enclosed combustion compartment, a burner operatively connected to said combustion compartment and constructed and arranged to produce combustion gases therewithin, an upright generally cylindrical wall extending vertically through said combustion compartment and iorrning an inner heating compartment, a generally enclosed hollow heat-exchange shell structure being formed by said cylindrical wall and the adjoining portion of said casing, a vertical baffle disposed generally at the median plane of the shell structure and dividing it into left and right half-sections provided with separate uppermost inlet openings, and at least one curved generally horizontal baie disposed within each of said half-sections and forming a plurality of vertically spaced communicating horizontal passageways therewithin, said shell structure being provided with a lowermost outlet opening disposed below the lower end of the vertical baiile and communicating with both of the half-sections, each of said half-sections being constructed and arranged to receive combustion gases through its uppermost opening and to conduct said gases alongV a generally downward tortuous path to said outlet opening thereby to heat both the outer and inner heating compartments.

6. A heater comprising a jacket forming an outer heating compartment, a casing disposed in spaced relationship within said jacket and forming an enclosed combustion compartment, a burner operatively connected to said combustion compartment and constructed and arranged to produce combustion gases therewithin, an upright generally cylindrical wall extending vertically through said combustion compartment and forming an inner heating compartment, a generally enclosed hollow heat-exchange shell structure being formed by said cylindrical wall and the adjoining portion of said casing, a vertical balde disposed generally at the median plane of the shell structure and dividing it into left and right half-sections provided with separate uppermost inlet openings, each of said half -sections being provided with a plurality of generally horizontal curved bailles forming a plurality of generally horizontal vertically-spaced passageways within each of said half-sections, successively downward passageways communicating with each other at alternate ends, said shell structure being provided with a lowermost outlet opening disposed below the lower end of the vertical baille and communicating with both of the halfsections, each of said half-sections being con- 10 structed and arranged to receive combustion gases through their uppermost openings and to conduct said gases along a generally downward tortuous path to said outlet opening thereby to heat both the outer and inner heating compart- 15 ments.

LOUIS DAVIDSON.

`REFlnmNoEs CITED Thefollowing references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 212,965 Merrill Mar. 4, 1879 308,039 Pease Nov. 11, 1884 424,737 Strang Apr. 1, 1890 1,140,239 Barth May 18, 1915 1,891,996 Miller Dec. 27, 1932 1,893,240 Hillier et al. Jan. 3, 1933 

